Chapter 12
List in sequential order the steps leading to transcription during transcriptional control of eukaryotic genes. Place the first step on the top of the list.
1. Transcription factors bind to promoters 2. Transcription activators bind to enhancers 3. Mediator proteins bind transcription activators to transcription factors. 4. RNA polymerase begins transcribing.
A certain gene excerpt has the sequence AAGGGTAACGA, then changes to CCGGGTAACGA. What just happened?
Correct Answer A gene mutation
The DNA sequence AAGTCTCAGGTC undergoes a point mutation. Which of the following could be the new sequence of DNA?
Correct Answer AAGTCTCTGGTC
A dark-staining portion of female, mammal nuclei containing an inactive X chromosome is called a:
Correct Answer Barr body
Identify the group of mammals that have a lower expression of immune system genes.
Correct Answer Bats
The first step of transcriptional control requires the presence of
Correct Answer Blank 1: DNA
A carcinogen is a type of mutagen that leads to the development of
Correct Answer Blank 1: cancer
Mutagens that leads to the development of cancer are called
Correct Answer Blank 1: carcinogens
Identical twins , having the same DNA can have different gene expression. The difference in gene expression in twins is due to __________ inheritance.
Correct Answer Blank 1: epigenetic , epigene, epi-genetic, or epigenes
Chromatin that is extended and transcribable is called
Correct Answer Blank 1: euchromati
Expressed regions of a mRNA that are conserved during mRNA processing are called
Correct Answer Blank 1: exons
Since it is highly condensed and inaccessible to RNA polymerase, the type of chromatin called _________ is seldom or never transcribed.
Correct Answer Blank 1: heterochromatin
The highly compacted chromatin that is not accessible for transcription is called
Correct Answer Blank 1: heterochromatin
An organism living in an environment free of mutagens would never experience
Correct Answer Blank 1: induced
Environmental influences, like toxic chemicals or radiation, are said to cause
Correct Answer Blank 1: induced
The noncoding regions, which are excised before the formation of mRNA, are called
Correct Answer Blank 1: introns
Chemical or physical agents that increase the chance of mutation are called
Correct Answer Blank 1: mutagens
Environmental factors such as radiation and organic chemicals can affect the nucleotide base composition of DNA and are therefore referred to as
Correct Answer Blank 1: mutagens or carcinogens
A permanent change to the base sequence of DNA is known as a gene
Correct Answer Blank 1: mutation
Posttranscriptional control takes place in the cell
Correct Answer Blank 1: nucleus or nuclei
Promoters, operators, and structural genes are the components of a(n)
Correct Answer Blank 1: operon
The functional unit of structural and regulatory prokaryotic genes is known as the
Correct Answer Blank 1: operon
When one base in a DNA sequence is altered, it is known as a
Correct Answer Blank 1: point
he enzyme that will carry out replication, proofread the new strand, and detect any mismatched nucleotides is DNA
Correct Answer Blank 1: polymerase
The stringy material called chromatin is composed of DNA and its associated
Correct Answer Blank 1: proteins or histones
The control of gene expression in cells is achieved through the process of gene
Correct Answer Blank 1: regulation
Gene mutations that occur during normal biological processes such as movement of transposons of DNA replication are called
Correct Answer Blank 1: spontaneous
Uncontrolled cell division and tumors can be caused by a mutation in the tumor
Correct Answer Blank 1: suppressor
Proteins that help regulate transcription by assisting the binding of RNA polymerase to the promotor are known as ______ factors.
Correct Answer Blank 1: transcription
The most critical of the five levels of eukaryotic gene expression control is
Correct Answer Blank 1: transcriptional or transcription
The level of eukaryotic control of gene expression that involves the control of the mRNA transcript in the cytoplasm of the cell is called ________ control.
Correct Answer Blank 1: translational or translation
The protein complex that not only assists with DNA replication, but also has the ability to repair spontaneous mutations is called ________.
Correct Answer DNA polymerase
Which of the following forms of chromatin would take up the most linear space (assuming same number of bases for each)?
Correct Answer Euchromatin
True or false: Lactose metabolism in E. coli is carried out by one enzyme product of one operon.
Correct Answer False
Which of the following is the most tightly packed chromatin?
Correct Answer Heterochromatin
Which set of genes have a lower expression in bats compared to other mammals? Multiple choice question. Blood type Fur color Immune system Developmental
Correct Answer Immune system
Which of the following is the last chance of influencing gene expression?
Correct Answer Posttranslational control
Which of the following would NOT be present in condensed eukaryotic chromatin?
Correct Answer RNA polymerase
Select the proteins that are required for the initiation of transcription by RNA polymerase in eukaryotes?
Correct Answer Transcription activator Transcription factor
Which of these levels of eukaryotic gene control occurs at the chromatin structure in the nucleus?
Correct Answer Transcriptional control
True or false: Although there are various levels of genetic control, transcriptional control is the most critical.
Correct Answer True
True or false: Gene regulation occurs in both prokaryotic cells and eukaryotic cells.
Correct Answer True
Which of the following have roles in transcriptional control of eukaryotic genes?
Correct Answer activators transcription factors DNA repressors
Chromatin structure helps control gene expression by:
Correct Answer allowing access to the DNA when it is not compacted
Which of the following are activities of posttranscriptional control mechanisms?
Correct Answer alternative mRNA splicing control of mRNA nuclear export speed
The structural genes found on the lac operon function to
Correct Answer break down lactose.
The DNA and its associated proteins are called
Correct Answer chromatin
Translational control occurs in the _____ of eukaryotic cells.
Correct Answer cytoplasm
The protein products of a certain bacterium depend upon its: Multiple choice question. introns exons environment abundance
Correct Answer environment
The transmission of genetic information outside of the coding sequence of a gene is referred to as ______.
Correct Answer epigenetic inheritance
Functional proteins are created from mRNA transcripts containing only:
Correct Answer exons
Barr bodies are normally present in
Correct Answer female mammals.
Small RNA is used to influence ______.
Correct Answer gene regulation
When the activators, enhancers, and mediators come in contact with the transcription factors the DNA forms a shape called a ______.
Correct Answer hairpin loop
When miRNA and siRNA molecules inhibit normal gene expression, RNA _______ has occurred.
Correct Answer interference
Heterochromatin is not transcribed because ______.
Correct Answer it is inaccessible to RNA polymerase.
Introns, noncoding regions, are excised before the exons are joined together to form ______.
Correct Answer mRNA
RNA interference occurs when ______ molecules interfere with normal gene expression.
Correct Answer miRNA and siRNA
A mutation that results in one base in the DNA being replaced by a different base is called a
Correct Answer point mutation.
Regulation that controls the way mRNA transcripts are processed in the nucleus called
Correct Answer posttranscriptional
Regulation that controls the way mRNA transcripts are processed in the nucleus called ________ control.
Correct Answer posttranscriptional
Alternative mRNA splicing takes place at which level of eukaryotic gene control?
Correct Answer posttranscriptional control
The level of eukaryotic control of gene expression that involves how a protein product is handled in a cell is called
Correct Answer posttranslational
Operons are generally involved with ______.
Correct Answer prokaryotic gene expression
Repressible operons require which of the following? Multiple select question. lactose enhancer repressor corepressor
Correct Answer repressor corepressor
Which of the following is formed from the DNA that is not used in transcription of a protein?
Correct Answer sRNA
If a mutation arises during DNA replication, then the mutation would considered a(n)______________ mutation.
Correct Answer spontaneous
An operon includes
Correct Answer structural genes operator promoter
Which of the following is an example of a repressible operon?
Correct Answer trp operon
The protein that restricts mitosis is coded for by the _______ gene.
Correct Answer tumor suppressor
Which of these levels of eukaryotic gene control is the most critical?
Transcriptional
True or false: Bacteria produce the same protein products regardless of their environment.
fALSE
